Ringschlüsse an Chinonylmethanfarbstoffen und analogen Merocyaninen. 2. Mitteilung. Dihydronaphthophenazinone; Beeinflussung der Löslichkeitseigenschaften durch Substitution,Isolierung und Charakterisierung einer Zwischenstufe des Ringschlusses

Cyclization Reactions of Quinonylmethane Dyes and Analogous Merocyanines. 2. Communication: Dihydro-oxo-naphto-phenazines. Correlation of Solubility and Substitution. Isolation and Characterization of an Intermediate Compound An intermediate compound of the cyclization reaction of 2-chloro-3-(1-cyclohexyl-3-methyl-1,2-dihydroquinoxalin-2-ylidenmethyl)-naphthoquinone was isolated and characterized by spectroscopic methods. 6-Chloro-8-cyclohexyl-5,8-dihydronaphtho[1,2-b]phenazinone was obtained as the final product of this reaction. Several more dihydronaphtho[1,2-b]phenazinone dyes were synthesized. The relationship of substitution and solubility of the dyes is discussed. The visible and ¹H-NMR. and some mass spectra of the dyes are given.